Is corruption an invincible enemy or is it more simply a very difficult enemy to defeat, to be faced with new strategies, without abandoning the old ones? The logic of administrative prevention appears today to be the most advanced frontier of anti-corruption policies. Fighting corruption through administration, and prevention, rather than through judicial and criminal prosecution: an ambitious goal, central for democratic systems.  The present Handbook is the outcome of the Winter School “Preventing Corruption through Administrative Measures” (2018), supported by the European Union Programme Hercule III (2014-2020) and organized by the Department of Political Science of the University of Perugia, in collaboration with the Regional Anti-corruption Initiative (RAI), European Anti-Fraud Office (OLAF), Italian National Anticorruption Authority (ANAC) and Villa Montesca. The volume aims, therefore, to provide tools, theoretical and operational, to address the challenge of preventing corruption.